Study finds low-dose Pharma drug best after transplant
By Gene Emery
BOSTON (Reuters) - Small doses of Astellas Pharma Inc's Prograf did a better job at preventing rejection of a transplanted kidney than varying doses of other drugs including a low dose of Wyeth's Rapamune, researchers said on Wednesday.
The research, published in Thursday's New England Journal of Medicine, is part of an effort to reduce the side effects of anti-rejection drugs like cyclosporine, which can damage the kidney with long-term use.
Doctors use a combination of drugs to prevent the immune system from rejecting transplanted kidneys.
Dr. Henrik Ekberg of Lund University in Malmo, Sweden, and his colleagues tested 1,645 transplant recipients at 83 medical centers in 15 countries.
They used four drug combinations, all of which included corticosteroids and Hoffmann-LaRoche's CellCept brand of mycophenolate mofetil.
Hoffmann-LaRoche paid for the study.
The rate of short-term rejection was lowest -- 12 percent -- in the group getting low-dose Prograf, known generically as tacrolimus. The rejection rate was twice as high for either low-dose cyclosporine or a regular dose of the drug. It was highest -- 37 percent -- for low-dose Rapamune, known generically as sirolimus.
After one year, the survival rate for the transplanted kidneys was 94.2 percent in the Prograf group, 93.1 percent among those getting low-dose cyclosporine, and 89.3 percent for both the regular cyclosporine recipients and the Rapamune patients.
"Serious adverse events were more common in the low-dose sirolimus group than in the other groups, although a similar proportion of patients in each group had at least one adverse event during treatment," the Ekberg team reported.
While sirolimus is not toxic to the kidneys the way cyclosporine and Prograf are, it has other side effects such as delayed wound healing, high cholesterol and diarrhea.
Dr. Alan Leichtman of the University of Michigan Medical School cautioned that the European study only lasted a year and longer-term results will be important. In addition, the findings may not be relevant in other countries, he said in a commentary.
While only 2 percent of the patients Ekberg studied were black, more than 35 percent of the people awaiting a transplant in the United States are black and may require higher doses of drugs that prevent rejection, Leichtman said.
(Editing by Maggie Fox, Richard Chang)